Deep brain stimulation (DBS), a surgery for Parkinson's disease in which wires attached to a device are inserted into your brain, can be life-changing for the right kind of patient. It may be an option for you if you've had Parkinson's for a minimum of four years, you don't have dementia, and your medications are still working for you — but not as well as they used to.
Deep brain stimulation for Parkinson's patients: What is it?
Deep brain stimulation, or DBS, is the most frequently used surgery to target the motor symptoms of Parkinson's disease, like tremors, rigidity, gait. It is not a cure, but it can significantly improve a patient's quality of life. The system "installed" in your body during DBS has four distinct parts:
- Thin wires (or "leads") with electrodes at their ends are placed in the portion of the brain that is causing your symptoms.
- Other wires will be inserted under your skin.
- These wires connect to a generator, or "brain pacemaker", which will be inserted near your neck or stomach, again under the skin.
- A remote control allows doctors to adjust the settings of the DBS system, and patients to turn the system on or off.
Who might be a candidate for deep brain stimulation?
You'll need to have in-depth conversations with your treating doctor to discover whether you may be a candidate for deep brain stimulation. In general terms, however:
- People in the early stages of Parkinson's disease have symptoms that can easily be managed with medications such as levodopa. They do not (yet) need deep brain stimulation.
- Levodopa becomes less effective after long-term use (leading patients to fluctuate between "on periods" and "off periods"), as well as often causing debilitating side effects. DBS may become an option at this stage.
- DBS is not considered a good option for people who suffer from dementia.
Where in the brain can DBS electrodes be placed?
The electrodes that will be placed in your brain with the aim of reducing your Parkinson's disease symptoms can be inserted into different areas of the brain, which also has different results:
- Electrodes in the globus pallidus (GPi) can reduce tremors, rigidity, slowness of movement, dyskinesia (involuntary movement) and dystonia (twisting and contracting muscle movements).
- Electrodes in the subthalamic nucleus (STN) can combat tremors, slowness of movement, dyskinesia, and dystonia — this site is used most often for Parkinson's.
- If electrodes are placed in the the pedunculopontine nucleus (PPN), in a relatively new variation of this procedure, patients may notice improvements in gait and freezing.
- Electrodes in the thalamus (VIM — ventro-intermediate nucleus) help with tremor.
Keep in mind that DBS is also used in the treatment of other movement disorders, the STN and GPi sites are usually chosen for Parkinson's patients.
How can you prepare for DBS?
Assessments to check whether you are the right candidate for surgery will be thorough, and are going to include blood tests, X-rays, and an EKG. Patients will also undergo an MRI scan to determine where the electrodes will be inserted — and then there's the usual pre-surgery stuff to consider, in the form of things like insurance, other paperwork, and providing your doctor with information about your personal medical history that may be relevant during the surgery (such as allergies to medications).
You'll stop eating and drinking the night prior to the operation, with the exception of small sips of water you may need to take to be able to swallow your medication. On the day itself, you'll shower with antibacterial soap, and make sure your body is free of nail polish, makeup, and jewelry. It is best if a friend or relative stays with you for support, beginning with driving you to the hospital. They can also keep a list of things you're allergic to and the prescription medications you're taking.
You will generally be expected to be at the hospital around two hours before surgery, but follow your surgical team's instructions to the letter.
What do you need to know about the surgery itself?
DBS is carried out by neurosurgeons who have specialized in functional neurosurgery. Exact surgical methods will vary, but it is important to know that patients are often awake during this particular surgery, both to help preserve brain function and because one of the techniques, brain mapping, necessitates this. Patients should also know that some techniques are completed over the course of two operations. You can usually expect the surgery to take up to four hours. Your surgeon can answer your questions about to expect, as they know what surgical method they will be employing.
How will the surgery affect how you look?
- While your whole head generally won't be shaved for DBS, some portions of hair will need to be shaved to allow the surgeon to gain access.
- Patients who have baldness may have a small visible scar after deep brain stimulation.
- The wire that connects your electrodes to your generator may be visible under certain circumstances after the surgery.
- While the generator itself can also be externally visible depending on the patient's weight, this is only while unclothed.
- You'll probably have puffy eyes after the surgery, which will resolve itself in a couple of days to a week.
What should you expect after deep brain stimulation surgery?
- The length of your hospital stay will depend on your condition as well as the technique used. You may be discharged as quickly as a day after surgery, or stay in hospital for a week or so.
- You should keep taking your prescribed Parkinson's medications after the surgery.
- Someone should drive you home, and you will likely need additional care at home while recovering.
- Your symptoms may improve right away.
- After the stimulator is implanted (whether during an all-in-one surgery or the second of two operations), your neurologist can adjust the settings and discuss the new dosage of your Parkinson's medications.
- You will regularly return to your neurologist to have the stimulator's settings adjusted.
What are the benefits of DBS?
Deep brain stimulation: The risks
Any surgery comes with potential risks as well as benefits, and deep brain stimulation is no exception. Death and stroke are the most daunting of these, with stroke being the result of bleeding within the brain in this case. While the exact risk of stroke is patient-specific, it is generally low, at only two percent.
Other potential complications of DBS include:
- Infection, seen in about four percent of cases. If this happens, your DBS system may have to be removed.
- Difficulties with speech.
- An allergic reaction to anesthesia.
- Confusion right after the surgery, caused by swelling in the brain that subsides over time.
Will DBS limit me in my daily life?
You'll have some restrictions in the post-operative periods. Patients who have just undergone DBS cannot fly in a plane, and should ask their surgeons when this is safe again. The incisions made during the operation must remain dry in the first week, so waterproof dressings are required, and patients should wear loose, comfortable, clothing while taking it easy.
The incisions can take around three weeks to heal completely, and at that point, you can resume your normal daily life — hopefully with much reduced symptoms. There's nothing you need to do differently during normal daily life, though patients should be aware that electronic security devices can sometimes lead to a DBS system being switched off. People with DBS systems should also generally steer clear of MRI scans, and always let their doctors know that they have a DBS if an MRI is proposed.